It is known that α-substituted esters are important as intermediates for pharmaceutical and agricultural chemicals. There have been reported, as conventional production techniques relevant to the present invention, a process of producing an optically active α-substituted ester by reaction of a trifluoromethanesulfonic acid ester of optically active α-hydroxyester with a Grignard reagent in the presence of a zinc catalyst (see Non-Patent Document 1). Various substitution reactions of fluorosulfuric acid esters of alcohols with nucleophilic reagents have also been reported (see Patent Document 1 and Non-Patent Document 2).